LAUSR

Abstract The magnetic properties of tetragonal polycrystalline intermetallic compound Tb 0.5 Ho 0.5 Mn 2 Si 2 have been investigated using temperature dependent dc magnetic susceptibility and neutron powder diffraction studies. Results of high temperature susceptibility data shows anomaly at T N  = 510 K while low temperature susceptibility data indicate two successive anomalies at T 1  = 11 K and T 2  = 25 K. Metamagnetic transition is observed in magnetization versus field curves. Our neutron diffraction results indicate three different magnetic regions with different magnetic structures. Neutron diffraction data shows that below T 2 , the intensities of some of the nuclear peaks get enhanced indicating ferromagnetic ordering, while additional magnetic reflections are observed below T 1 , indicating antiferromagnetic order. Ordering of rare earth sublattice at low temperature rearranges the ordering of Mn sublattice and results in reorientation of Mn spins at T 1 . At 2 K Tb/Ho moments are aligned along c-axis while Mn moments are aligned perpendicular to c-axis.